Laminating system, ic sheet, scroll of ic sheet, and method for manufacturing ic chip

ABSTRACT

Thin film integrated circuits are peeled from a substrate and the peeled thin film integrated circuits are sealed, efficiently in order to improve manufacturing yields. The present invention provides laminating system comprising transporting means for transporting a substrate provided with a plurality of thin film integrated circuits; first peeling means for bonding first surfaces of the thin film integrated circuits to a first sheet member to peel the thin film integrated circuits from the substrate; second peeling means for bonding second surfaces of the thin film integrated circuits to a second sheet member to peel the thin film integrated circuits from the first sheet member; and sealing means for interposing the thin film integrated circuits between the second sheet member and a third sheet member to seal the thin film integrated circuit with the second sheet member and the third sheet member.

TECHNICAL FIELD

The present invention relates to a laminating system for peeling andsealing thin film integrated circuits provided over a substrate, an ICsheet including a plurality of sealed thin film integrated circuits, ascroll of an IC sheet including a plurality of sealed thin filmintegrated circuits, and a method for manufacturing an IC chip whichseals thin film integrated circuits.

BACKGROUND ART

In recent years, the necessity of an IC chip mounted card or an IC chipmounted tag which can transmit data out of touch has been grown in afield which needs automatic recognition such as securities and commoditymanagement. The IC chip mounted card reads and writes data to/from anexternal device via a loop antenna in the card. The IC chip mounted cardhas larger memory capacity and higher security than those of a magneticcard that records data by a magnetic encoding method. Hence, it has beenproposed that a form of the IC mounted card capable of being applied tovarious fields. (For example, refer to Patent document 1.)

Generally, an IC chip is formed by a silicon wafer. In recent years,technological development of an IC chip using a thin film integratedcircuit provided over a glass substrate (an IC tag, an ID tag, a RF tag(Radio Frequency), a wireless tag (also referred to as an electric tag))has been promoted for reduction in cost. According to such thetechnology, the thin film integrated circuit provided over the glasssubstrate is required to separate from the glass substrate which is asupport substrate after being completely manufactured. Therefore,various techniques have been contrived as a method for separating thethin film integrated circuit provided over the support substrate.

For example, as a method for peeling the thin film integrated circuitprovided over the support substrate, there is the technique by which apeeling layer made from amorphous silicon (or polysilicon) is formed andhydrogen included in the amorphous silicon is released by laserirradiation to produce empty spaces to separate the support substratefrom the peeling layer (Patent document 2). Alternatively, there is thetechnique by which a peeling layer containing silicon is formed betweena thin film integrated circuit and a support substrate, and the peelinglayer is removed with gas containing halogen fluoride to separate thethin film integrated circuit from the support substrate (Patent document3).

Patent document 1: Unexamined patent publication No. 2001-260580

Patent document 2: Unexamined patent publication No. 10-125929

Patent document 3: Unexamined patent publication No. 8-254686

However, in the case that a plurality of thin film integrated circuitsare formed over a substrate, the plurality of the thin film integratedcircuits are separated from the substrate individually by removing thepeeling layer. When the separated thin film integrated circuits arerespectively sealed by laminate treatment or the like, manufacturingefficiency is deteriorated. Since the separated thin film integratedcircuits are thin and lightweight, it is extremely difficult to sealthem without damaging or breaking.

From the point of view of production efficiency, peeling and sealingprocesses for thin film integrated circuits provided over a substrateare carried out in succession by using a sequence of equipment.Generally, the sealing process by a laminate processing is carried outwith a film having strong adhesion force such as a hot melt film inconsideration of strength and reliability after sealing. Hence, whenpeeling process for the thin film integrated circuits is also carriedout with a film having strong adhesion force, peeling of the thin filmintegrated circuits may be failed because the film may adhere to thesubstrate. As a result, there arises a problem that manufacturing yieldsare deteriorated. In the case that the peeling and sealing processes forthin film integrated circuits are carried out with a film having weakadhesion, the thin film integrated circuits can be effectively peeledfrom the substrate; however, there arises a problem in reliability ofsealed thin film integrated circuits.

DISCLOSURE OF INVENTION

In view of the foregoing, it is an object of the present invention toprevent deterioration of manufacturing efficiency when sealing thin filmintegrated circuits and to prevent damage and destruction of the thinfilm integrated circuits. Further, it is another object of the presentinvention to peel the thin film integrated circuits from a substrate andseal the peeled thin film integrated circuits and to improvemanufacturing yields.

One embodiment of the present invention provides a laminating systemcomprising transporting means for transporting a substrate provided witha plurality of thin film integrated circuits; first peeling means forbonding first surfaces of the thin film integrated circuits to a firstsheet member to peel the thin film integrated circuits from thesubstrate; second peeling means for bonding second surfaces opposed tothe first surfaces of the thin film integrated circuits to a secondsheet member to peel the thin film integrated circuits from the firstsheet member; and sealing means for interposing the thin film integratedcircuits between the second sheet member and a third sheet member toseal the thin film integrated circuits with the second sheet member andthe third sheet member.

Another embodiment of the present invention provides a laminating systemcomprising transporting means for transporting a substrate provided witha plurality of thin film integrated circuits; a first supply rollerwounded with a first sheet member; first peeling means for bonding firstsurfaces of the thin film integrated circuits to the first sheet memberto peel the thin film integrated circuits from the substrate; a secondsupply roller wounded with a second sheet member; second peeling meansfor bonding second surfaces opposed to the first surfaces of the thinfilm integrated circuits to a second sheet member to peel the thin filmintegrated circuits from the first sheet member; a third supply rollerwounded with a third sheet member; sealing means for interposing thethin film integrated circuits between the second sheet member and thethird sheet member to seal the thin film integrated circuits with thesecond sheet member and the third sheet member; and a receiving rollerfor winding the thin film integrated circuits which are sealed with thesecond sheet member and the third sheet member.

More another embodiment of the present invention provides a laminatingsystem comprising a substrate provided with a plurality of thin filmintegrated circuits; a first supply roller wounded with a first sheetmember; fixating and moving means for fixating the substrate so that onesurface of the substrate is opposite to the first sheet member and formoving the substrate so that the plurality of thin film integratedcircuits and the first sheet member are bonded together; first peelingmeans for bonding first surfaces of the thin film integrated circuits tothe first sheet member to peel the thin film integrated circuits fromthe substrate; a second supply roller wounded with a second sheetmember; second peeling means for bonding second surfaces opposed to thefirst surfaces of the thin film integrated circuits to the second sheetmember to peel the thin film integrated circuits from the first sheetmember; a third supply roller wounded with a third sheet member whichbonds to the first surfaces of the thin film integrated circuits;sealing means for sealing the thin film integrated circuits with thesecond sheet member and the third sheet member; and a receiving rollerfor winding the thin film integrated circuits which are sealed with thesecond sheet member and the third sheet member.

In the laminating system having the foregoing embodiments, the sealingmeans has at least two rollers provided so as to be opposed to eachother. Either or both of the two rollers has a heating means. Thesealing means passes the thin film integrated circuits through the tworollers and seals the thin film integrated circuits by performing eitheror both of a pressure treatment and a heating treatment.

Further more another embodiment of the present invention provides alaminating system comprising transporting means for transporting asubstrate provided with a plurality of thin film integrated circuits; afirst supply roller wounded with a first sheet member; first peelingmeans for bonding first surfaces of the thin film integrated circuits tothe first sheet member to peel the thin film integrated circuits fromthe substrate; a second supply roller wounded with a second sheetmember; second peeling means for bonding second surfaces opposed to thefirst surfaces of the thin film integrated circuits to a second sheetmember to peel the thin film integrated circuits from the first sheetmember; means for supplying resin in a heated and melted state bysqueezing onto the first surfaces of the thin film integrated circuits;sealing means for sealing the thin film integrated circuits with thesecond sheet member and the resin; and a receiving roller for windingthe thin film integrated circuits which are sealed with the second sheetmember and the resin. In that case, the sealing means has at least tworollers provided so as to be opposed to each other, and either or bothof the two rollers has a cooling means. The sealing means passes thethin film integrated circuits through the two rollers and seals the thinfilm integrated circuits by performing either or both of a pressuretreatment and a heating treatment.

In the laminating system according to the present invention, the firstpeeling means and the second peeling means have rollers. Further, thesecond peeling means has at least two rollers so as to be opposed toeach other, passes the thin film integrated circuits through the tworollers, and seals the thin film integrated circuits by performingeither or both of a pressure treatment and a heating treatment.

The first sheet member has at least one side with an adhesive property.The second sheet member and the third sheet member are laminate films.

The present invention provides an IC sheet which is formed by forming aplurality of sealed thin film integrated circuits into a sheet to makeit easier for the IC sheet to be used. The IC sheet according to thepresent invention is composed of two sheet members of a second sheetmember and a third sheet member which seal a plurality of the thin filmintegrated circuits therebetween.

The present invention provides a scroll of an IC sheet which is formedby winding an IC sheet including a plurality of thin film integratedcircuits sealed with two sheet members to make it easier for the scrollof an IC sheet to be used. The scroll of an IC sheet according to thepresent invention is formed by winding an IC sheet obtained by sealingthe plurality of thin film integrated circuit between the two sheetmembers of the second sheet member and the third sheet member.

In the IC sheet or a scroll of an IC sheet having the foregoingembodiments, each of a plurality of the thin film integrated circuitshas a plurality of thin film transistors and a conductive layer servingas an antenna, and each of the plurality of thin film integratedcircuits is regularly arranged.

A method for manufacturing an IC chip comprises the steps of forming apeeling layer over a substrate having an insulating surface; forming aplurality of thin film integrated circuits over the substrate; formingan opening portion at a boundary between the thin film integratedcircuits to expose the peeling layer; introducing gas or liquidcontaining halogen fluoride into the opening portion to remove thepeeling layer; bonding first surfaces of the thin film integratedcircuits to a first sheet member to peel a plurality of the thin filmintegrated circuits from the substrate; bonding second surfaces opposedto the first surfaces of the thin film integrated circuits to a secondsheet member to peel the thin film integrated circuits from the firstsheet member; bonding the first surfaces of the thin film integratedcircuits to a third sheet member to seal the thin film integratedcircuits with the second sheet member and the third sheet member.Further, a plurality of thin film transistors and a conductive layerserving as an antenna are formed as the thin film integrated circuitsover the substrate.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a view for showing a laminating system according to thepresent invention;

FIG. 2 is a view for showing a laminating system according to thepresent invention;

FIG. 3 is a view for showing a laminating system according to thepresent invention;

FIG. 4 is a view for showing a laminating system according to thepresent invention;

FIGS. 5A and 5B are views for showing an IC sheet according to thepresent invention;

FIGS. 6A and 6B are views for showing a scroll of an IC sheet accordingto the present invention;

FIGS. 7A to 7C are views for showing a method for manufacturing an ICchip according to the present invention;

FIGS. 8A to 8C are views for showing a method for manufacturing an ICchip according to the present invention;

FIGS. 9A and 9B are views for showing a method for manufacturing an ICchip according to the present invention;

FIGS. 10A and 10B are views for showing a peeling method according tothe present invention;

FIGS. 11A and 11B are views for showing a top view of an IC chipaccording to the present invention;

FIGS. 12A to 12E are views for showing articles mounted with thin filmintegrated circuits according to the present invention;

FIGS. 13A and 13B are views for showing articles mounted with thin filmintegrated circuits according to the present invention;

FIG. 14 is a view for showing a cross-structure of an IC chip accordingto the present invention;

FIGS. 15A and 15B are views for showing a cross-structure of an IC chipaccording to the present invention; and

FIGS. 16A and 16B are views for showing a cross-structure of an IC chipaccording to the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

The above and further objects and novel features of the invention willmore fully appear from the following details description when the sameis read in connection with the accompanying drawings. As the presentinvention may be embodied in several forms, it is to be understood thatvarious changes and modifications will be apparent to those skilled inthe art without departing from the spirit of essential characteristicsof the present invention. Therefore, unless otherwise such changes andmodifications depart from the scope of the present invention hereinafterdescribed, they should be construed as being included therein. Throughthe drawings of the embodiments, like components are denoted by likenumerals as of the first embodiment and will not be further explained.

The present invention provides a laminating system which continuouslypeels thin film integrated circuits provided over a substrate and sealsthe peeled thin film integrated circuits. According to the presentinvention, a plurality of thin film integrated circuits provided over asubstrate is bonded to a first sheet member to be peeled from thesubstrate, and the thin film integrated circuits bonded to the firstsheet member is bonded to a second sheet member to be peeled once againfrom the first sheet member, then, a third sheet member is bonded to asurface opposite to the surface bonded with the second sheet member, andthen, the thin film integrated circuit is sealed with the second sheetmember and the third sheet member by a sealing means. That is, peelingof the thin film integrated circuits is performed twice in a process ofa series of the peeling and the sealing.

The first sheet member is used to peel the thin film integrated circuitsprovided over the substrate. The second sheet member is used to peel thethin film integrated circuits from the first sheet member and serves asa laminate film for sealing the thin film integrated circuits with thethird sheet member. The reason that the peeling is performed twice isthat the laminate film for sealing has so strong adhesive force that thethin film integrated circuits provided over the substrate cannot beefficiently peeled from the substrate since the laminate film adheresnot only to the thin film integrated circuits but also to the substrate.Therefore, the first sheet member with a weak adhesive surface is usedto peel the thin film integrated circuits over the substrate and thesecond sheet member formed by a laminated film or the like is used topeel again the thin film integrated circuits from the first sheetmember.

According to the present invention, the laminated film used as thesecond or third sheet member may be any film as long as it can be usedfor laminating. For example, a material such as polypropylene,polystyrene, polyester, vinyl, polyvinyl fluoride, vinyl chloride,methyl methacrylate, nylon, or polycarbonate can be used as the laminatefilm. The second or third sheet member has one adhesive surface. Theadhesive surface may be coated with an adhesive agent such asthermosetting resin, ultraviolet curing resin, an epoxy resin adhesiveagent, a photocuring adhesive agent, a moisture curing adhesive agent,or a resin addition agent.

The present invention includes an IC sheet formed by sealing a pluralityof thin film integrated circuits to have a sheet-like shape or an ICscroll formed by winding an IC sheet having a plurality of thin filmintegrated circuits.

According to the present invention, an IC chip can be manufactured byforming thin film integrated circuits over a substrate via a peelinglayer, and removing the peeling layer to peel the thin film integratedcircuits from the substrate, then, sealing the thin film integratedcircuits.

Hereinafter, a laminating system for continuously peeling and sealing aplurality of thin film integrated circuits over a substrate, an IC sheethaving the sealed plurality of thin film integrated circuits, and amanufacturing method for a scroll of the IC sheet and an IC chip arespecifically explained with reference to the drawings.

Embodiment 1

In this embodiment, a main form of a laminating system for continuouslyperforming processes of peeling thin film integrated circuits from asubstrate and sealing the peeled thin film integrated circuits will behereinafter explained.

The laminating system according to this embodiment has a transportingmeans 11 for transporting a substrate 12 provided with a plurality ofthin film integrated circuits 13, a first supply roller 14 winded with afirst sheet member 18, a first peeling means 51 provided with a roller16 for bonding the thin film integrated circuits 13 to the first sheetmember 18 to peel the thin film integrated circuits 13 from thesubstrate 12, a second supply roller 15 winded with a second sheetmember 19, a second peeling means 52 provided with rollers 24, 28 forbonding the thin film integrated circuits 13 to a second sheet member 19to peel the thin film integrated circuits 13 from the first sheet member18, a receiving roller 21 for collecting the first sheet member 18, athird supply roller 22 for supplying a third sheet member 23, a sealingmeans 17 for sealing the thin film integrated circuits 13 with thesecond sheet member 19 and the third sheet member 23, and a receivingroller 20 for winding the sealed thin film integrated circuits 13.

In the system illustrated in FIG. 1, the first sheet member 18 suppliedfrom the first supply roller 14 is bonded to the thin film integratedcircuits 13 over the substrate 12 transported by the transporting means11 to peel the thin film integrated circuits 13 from the substrate 12with the first peeling means 15 provided with the roller 16. Thereafter,the peeled thin film integrated circuits 13 are bonded to the firstsheet member 18 to pass through the roller 28. The second sheet member19 supplied from the second supply roller 15 passes through the roller24.

The second sheet member 19 is bonded to the opposite side of thetransported thin film integrated circuits 13 which is bonded to thefirst sheet member 18 to peel the thin film integrated circuits 13 fromthe first sheet member 18 by the second peeling means 52 provided withthe rollers 24, 28. Either or both of pressure treatment and heattreatment is carried out when bonding the thin film integrated circuits13 bonded to the first sheet member 18 to the second sheet member 19.Thereafter, the peeled thin film integrated circuits 13 are bonded tothe second sheet member 19 and passed through the sealing means 17.Further, the third sheet member 23 supplied from the third supply roller22 passes through the sealing means 17.

The sealing means 17 bonds a side opposite to the side of thetransported thin film integrated circuits 13 bonded to the second sheetmember 19 (the side opposite to the side bonded to the second sheet 19)to the third sheet member 23. Simultaneously, either or both of pressuretreatment and heat treatment are carried out. Thereafter, the sealedthin film integrated circuits 13 pass through the receiving roller 20and wind around the receiving roller 20.

In the laminating system illustrated in FIG. 1, as noted above, thefirst sheet member 18 is supplied from the first supply roller, andpassed through the roller 16 and the roller 28 included in the firstpeeling means sequentially, then, collected by the receiving roller 21.The first supply rollers 14 and the rollers 16, 28 are spun to the samedirections. The second sheet member 19 is supplied from the secondsupply roller 15, and passed through the roller 24 included in thesecond peeling means and the roller 25 included in the sealing means 17sequentially, then, collected by the receiving roller 20. The secondsupply roller 15 and the rollers 24, 25 are spun to the same directions.The third sheet member 23 is supplied from the third supply roller 22,and passed through the roller 26 included in the sealing means 17, then,collected by the receiving roller 20. The third supply roller 22 and theroller 26 are spun to the same directions.

The transporting means 11 transports the substrate 12 provided with aplurality of the thin film integrated circuits 13. In FIG. 1, thetransporting means 11 has a roller 27. The substrate 12 is transportedby spinning the roller 27. The transporting means 11 may have anystructure as long as it can transport the substrate 12. For example, abelt conveyor, a plurality of roller, a robot arm, or the like can beused as the transporting means 11. The robot arm transports thesubstrate 12 or a stage provided with the substrate 12. Further, thetransporting means 11 transports the substrate 12 at predetermined speedin accordance with the transporting speed of the first sheet member 18.

The first sheet member 18, the second sheet member 19, and the thirdsheet member 23 respectively wind around the first supply roller 14, thesecond supply roller 15, and the third supply roller 22. The first sheetmember 18 is moved toward the roller 28 included in the second peelingmeans at predetermined speed by spinning the first supply roller 14 atpredetermined speed. Each of the second sheet member 19 and the thirdsheet member 23 is moved toward the sealing means 17 at predeterminedspeed by spinning the second supply roller 15 and the third supplyroller 22 at predetermined speed. The first supply roller 14, the secondsupply roller 15, and the third supply roller 22 are in columnar shapesand made from a resin material, a metal material, a rubber material, orthe like.

The first sheet member 18 is formed by a flexible film and has at leastone surface with an adhesive property. Specifically, the adhesivesurface is prepared by providing an adhesive agent on a base film usedas a base material such as polyester. As the adhesive agent, a resinmaterial or a synthetic rubber material containing acrylic resin or thelike can be used. Further, a film having weak adhesive force(preferably, 0.01 to 1.0 N, more preferably, 0.05 to 0.75 N, morepreferably, 0.15 to 0.5 N) is preferably used as the first sheet member18 in order to bond the thin film integrated circuits again to thesecond sheet member to peel the first sheet member from the thin filmintegrated circuits after bonding the thin film integrated circuitsprovided over the substrate to the first sheet member. The thickness ofthe adhesive agent may be 1 to 100 μm, preferably, 5 to 50 μm, morepreferably, 10 to 30 μm. Preferably, the base film is formed by apolyester film or the like with a thickness of 10 μm to 1 mm,preferably, 25 to 200 μm, more preferably, 50 to 100 μm for easyhandling in processing.

As the first sheet member, a UV (ultraviolet) peeling film, a thermalpeeling film, or the like can be used in addition to the foregoingmaterials. The UV peeling film is prepared by forming an adhesive layermade from a resin material which loses its adhesive force by UVirradiation over the base film. The thermal peeling film is prepared byforming an adhesive layer made from a resin material which loses itsadhesive force by heat over the base film.

In the case that the surface of the adhesive layer is protected by aseparator, a separator receiving roller 30 is provided as illustrated inFIG. 1 to remove the separator 29 in use. Further, a base film subjectedto antistatic treatment used as the base material can be used as theseparator. The separator is formed by a film or a paper made frompolyester or the like. The separator is preferably formed by a film madefrom polyethylene terephthalate or the like since there can be no paperpowder in patterning.

The second sheet member 19 and the third sheet member 23 are formed byflexible films, for example, a laminate film, a paper made from afibrous material, or the like. The laminate film means films in generalwhich can be used for laminate treatment. The laminate film is made froma material such as polypropylene, polystyrene, polyester, vinyl,polyvinyl fluoride, vinyl chloride, methyl methacrylate, nylon,polycarbonate, or he like, and the surface of the laminate film may besubjected to processing treatment such as embossing.

In this embodiment, the thin film integrated circuits are preferablysealed with a hot melt adhesive. The hot melt adhesive is a chemicalsubstance which does not contain water or a fluxing material, which ismade from a nonvolatile thermoplastic material being solid in a roomtemperature, and which bonds things together by being coated in amelting state to be cooled. The hot melt adhesive has advantages ofbeing unstuck easily, nonpolluting, safe, clean, energy-saving, and lowcost.

Since the hot melt adhesive is solid at normal temperature, the hot meltadhesive which is formed to be a film or fibrous in advance, or which isformed to be a film by forming an adhesive layer over a base film madefrom polyester or the like can be used. Here, a sheet member prepared byforming a hot melt film over a base film made from polyethyleneterephthalate is used. The hot melt film is made from resin having alower softening point than that of the base film, and melted into arubber state when being applied with heat to be bonded and hardened whenbeing cooled. As the hot melt film, a film mainly containing, forexample, ethylene-vinyl acetate copolymer (EVA) series, polyesterseries, polyamide series, thermoplastic elastomer series, polyolefinseries, or the like can be used.

Either or both of the second sheet member 19 and the third sheet member23 may have one adhesive surface. The adhesive surface can be preparedby coating either surface of either or both of the second sheet member19 and the third sheet member 23 with thermosetting resin, ultravioletcuring resin, an epoxy resin adhesive agent, a photocuring adhesiveagent, a moisture curing adhesive agent, or a resin addition agent.

Either or both of the second sheet member 19 and the third sheet member23 may have a light transmitting property. In order to protect the thinfilm integrated circuits 13 to be sealed, either or both of the secondsheet member 19 and the third sheet member 23 may be coated with aconductive material by charging static electricity. Either or both ofthe second sheet member 19 and the third sheet member 23 may be coatedwith a thin film mainly containing carbon (diamond like carbon film) ora conductive material such as indium tin oxide (ITO) as a protectivefilm.

The first peeling means 51 has at least the roller 16 to bond eithersurfaces of the thin film integrated circuits 13 to either surface ofthe first sheet member 18 to peel the thin film integrated circuits 13from the substrate 12. By spinning the roller 16, the thin filmintegrated circuits 13 are bonded to the first sheet member 18 to bepeeled from the substrate 12. Therefore, the roller 16 is provided to beopposite to the side over which the thin film integrated circuits 13 areprovided of the substrate 12. Further, the roller 16 is in a columnarshape and made from a resin material, a metal material, a rubbermaterial, or the like, preferably, a soft material.

The second peeling means 52 has at least the rollers 24, 28 opposing toeach other to bond the thin film integrated circuits 13 to eithersurface of the second sheet member 19 to peel the thin film integratedcircuits 13 from the first sheet member 18. In that case, the thin filmintegrated circuits 13 are bonded to the second sheet member 19 which issupplied from the second supply roller 15 and is passed through theroller 24, simultaneously, either or both of pressure treatment and heattreatment is carried out by using either or both of the rollers 24, 28when the second sheet member 19 passes through the rollers 24, 28.

According to this treatment, the thin film integrated circuits 13 bondedto the first sheet 18 is bonded to the second sheet member 19. As theheat treatment, any method as long as it can apply heat energy can beused. For example, warm media such as an oven, a heater of a heatingwire, or oil; a hot stamp; a thermal head; laser light; an infraredflash; a heat stylus; or the like can be used. Further, the rollers 24,28 are in columnar shapes and made from a resin material, a metalmaterial, a rubber material, or the like, preferably, a soft material.

When the thin film integrated circuits 13 which is bonded to the secondsheet member 19 at second surfaces of the thin film integrated circuits13 is moved toward the sealing means 17, the sealing means 17 bonds thethird sheet member 23 to the first surfaces of the thin film integratedcircuits 13, simultaneously, the thin film integrated circuits 13 aresealed with the second sheet member 19 and the third sheet member 23.The sealing means 17 has the rollers 25, 26 opposing to each other. Theother surface of the thin film integrated circuits 13 is bonded to thethird sheet member 23 which is supplied from the third supply roller 22and is passed through roller 26, simultaneously, either or both ofpressure treatment and heat treatment is carried out by using therollers 25, 26 when the third sheet member 23 passes between the rollers25, 26. According to the treatment, the thin film integrated circuits 13are sealed with the second sheet member 19 and the third sheet member23.

Either or both of the rollers 25, 26 composing the sealing means 17 havea heating means. As the heating means, warm media such as an oven, aheater of a heating wire, or oil; a hot stamp; a thermal head; laserlight; an infrared flash; a heat stylus; or the like can be used. Therollers 25, 26 are spun at predetermined speed in accordance with thespinning speed of the roller 24, the second supply roller 15, and thethird supply roller 22. The rollers 25, 26 are in columnar shapes andmade from a resin material, a metal material, a rubber material, or thelike, preferably, a soft material.

The receiving roller 20 is a roller for winding and collecting the thinfilm integrated circuits 13 sealed with the second sheet member 19 andthe third sheet member 23. The receiving roller 20 spins atpredetermined speed in accordance with the spinning speed of the rollers25, 26. The receiving roller 20 is in a columnar shape and made from aresin material, a metal material, a rubber material, or the like,preferably, a soft material.

As noted above, a plurality of the thin film integrated circuits 13provided over the substrate 12 can be continuously peeled, sealed, andcollected by the spin of the first to third supply rollers 14, 15, and21, the rollers 16, 24, 28, 25, and 26, and the receiving roller 20. Thesystem illustrated in FIG. 1 has high mass productivity and can improvemanufacturing efficiency.

A laminating system which has a different form from that of theforegoing laminating system is explained with reference to FIG. 2.

The laminating system illustrated in FIG. 2 has a fixating and movingmeans 33 for the substrate 12, a first peeling means 51 for peeling thethin film integrated circuits 13 from one surface of the substrate 12, afirst supply roller 14 winded with a first sheet member 18, a secondsupply roller 15 winded with a second sheet member 19, a second peelingmeans 52 for peeling the thin film integrated circuits 13 from the firstsheet member 18 and bonding the thin film integrated circuits 13 to thesecond sheet member 19, a sealing means 17 for sealing the thin filmintegrated circuits 13 between the second sheet member 19 and a thirdsheet member 23, and a receiving roller 20 for collecting the sealedthin film integrated circuits 13. The structure illustrated in FIG. 2 isnewly added with the fixating and moving means 33 in FIG. 1.

In the system illustrated in FIG. 2, the first sheet member 18 which issupplied from the first supply roller 14 and which passes through aroller 16 is bonded with the substrate 12 by the fixating and movingmeans 33. Accordingly, the thin film integrated circuits 13 are bondedto the first sheet member 18 by the first peeling means 51 provided withthe roller 16 to be peeled from the substrate 12. The first sheet member18 bonded with the peeled thin film integrated circuits 13 is movedtoward the roller 28. Further, the second sheet member 19 supplied fromthe second supply roller 15 is moved toward the roller 24. Then, thethin film integrated circuits 13 are sealed as illustrated in FIG. 1.

The fixating and moving means 33 serves to fix the substrate 12 so thatthe surface of the substrate 12 over which the thin film integratedcircuits 13 are provided (hereinafter, either surface) is placedopposite to the first sheet member 18 and serves to move the substrate12 to bond the thin film integrated circuits 13 to the first sheetmember 18. The substrate 12 is moved by moving the fixating and movingmeans 33. As shown in FIG. 2, a means which processes the substrate 12one-by-one, or a means which is composed of a cylindrical object or apolyhedron such as a rectangular object can be used as the fixating andmoving means 33. In the case that a cylindrical or polyhedral fixatingand moving means 33 is used, the substrate 12 is fixated to the side ofthe fixating and moving means 33 to be moved by spinning the cylindricalor polyhedral fixating and moving means 33.

As noted above, in the laminate system illustrated in FIG. 2, the thinfilm integrated circuits 13 can be continuously peeled, sealed, andcollected by spinning the fixating and moving means 33, the first tothird supply rollers, the rollers 16, 24, 28, 25, and 26, and thereceiving roller 20. Therefore, mass productivity and manufacturingefficiency can be improved by using the laminate system illustrated inFIG. 2.

A laminating system which has a different form from that of theforegoing laminating system is explained with reference to FIG. 3.

The laminating system illustrated in FIG. 3 has a transporting means 11for transporting the substrate 12, a first peeling means 51 for peelingthe thin film integrated circuits 13 from either surface of thesubstrate 12, a first supply roller 14 winded with the first sheetmember 18, a second supply roller 15 winded with the second sheet member19, a second peeling means 52 for peeling the thin film integratedcircuits 13 from the first sheet member 18 and bonding the peeled thinfilm integrated circuits 13 to the second sheet member 19, a sealingmeans 17 for sealing the thin film integrated circuits 13 with thesecond sheet member 19 and resin 55 which is squeezed in a state ofbeing heated onto the surface of the thin film integrated circuits 13opposite to the surface bonded to the second sheet member 19, and areceiving roller 20 for winding the sealed thin film integrated circuits13. The structure illustrated in FIG. 3 is a structure as illustrated inFIG. 1 except that dye 54 and the resin 55 are substituted for the thirdsupply roller 22 and the third sheet member 23.

The system illustrated in FIG. 3 can conduct processes in accordancewith those illustrated in FIG. 1 up to peel the thin film integratedcircuits 13 provided over the substrate 12 by the first sheet member 18,to bond the thin film integrated circuits 13 bonded to the first sheetmember 18 to the second sheet member 19, and to move the thin filmintegrated circuits 13 bonded to the second sheet member 19 toward thesealing means 17. Thereafter, in FIG. 3, heated to be melted resin 55 issqueezed from dye 54 onto the first surface (surface opposite to thesecond surface bonded with the second sheet member). Then, the secondsheet member 19 and the resin 55 introduced between a crimping roller 56and a cooling roller 57 is cooled while applying pressure by thecrimping roller 56 and the cooling roller 57 to bond the resin 55 to thefirst surface of the thin film integrated circuits 13, simultaneously,the thin film integrated circuits 13 are sealed with the second sheetmember 19 and the resin 55. Lastly, the sealed thin film integratedcircuits 13 is moved toward the receiving roller 20 to be winded andcollected by the receiving roller 20.

In the structure of the laminating system illustrated in FIG. 3,thermoplastic resin is used as the resin 55. Thermoplastic resin havinga low softening point is preferably used as the resin 55. For example,polyolefin resin such as polyethylene, polypropylene, orpolymethylpentene; vinyl copolymer such as vinyl chloride, vinylacetate, polyvinyl chloride acetate copolymer, ethylene-vinyl acetatecopolymer, vinylidene chloride, polyvinyl butyral, or polyvinyl alcohol;acrylic resin; polyester resin; urethane resin; cellulosic resin such ascellulose, cellulose acetate, cellulose acetate butyrate, celluloseacetate propionate, or ethyl cellulose; styrene resin such aspolystyrene or acrylonitrile-styrene copolymer can be nominated. Theresin 55 may be a single layer squeezed from the dye 54, alternatively,two or more layers squeezed together from the dye 54. Further, any oneof the foregoing materials can be used as the first sheet member 18 orthe second sheet member 19.

As noted above, according to the laminating system illustrated in FIG.3, a plurality of the thin film integrated circuits 13 provided over thesubstrate 12 can be continuously peeled, sealed, and collected by thespin of the transporting means 11, the first and second supply rollers14, 15, the rollers 16, 24, and 28, the crimping roller 56, the coolingroller 57, and the receiving roller 20. Therefore, the systemillustrated in FIG. 3 can improve mass productivity and manufacturingefficiency.

Then, an overall structure of the laminate system is explained withreference to FIG. 4. Here, the structure of laminate system includingthe structure illustrated in FIG. 1 is cited as an example for theexplanation.

A cassette 41 is a cassette for supplying a substrate in whichsubstrates 12 provided with a plurality of the thin film integratedcircuits 13 are placed. The cassette 42 is a cassette for collecting asubstrate, which collects the substrate 12 after separating from thethin film integrated circuits 13. A plurality of rollers 43 to 45 isprovided between the cassette 41 and 42 as a transporting means. Thesubstrate 12 is transported by the spin of the rollers 43 to 45.Thereafter, as noted above, the thin film integrated circuits 13 arepeeled and sealed, and the sealed thin film integrated circuits 13 arecut by a cutting means 46. The cutting means 46 uses a dicing machine,scribing machine, a laser irradiation machine (CO₂ laser irradiationmachine), or the like. The sealed thin film integrated circuits 13 arecompleted in accordance with the foregoing processes.

In the foregoing structure illustrated in FIGS. 1 to 3, the thin filmintegrated circuits 13 provided over the substrate 12 include an elementgroup composed of a plurality of elements and a conductive layer servingas an antenna. However, the present invention is not restricted to thestructure.

The thin film integrated circuits 13 provided over the substrate 12 mayinclude only the element group. The conductive layer serving as anantenna is pasted onto the second sheet member 19 or the third sheetmember 23, and a plurality of the elements included in the thin filmintegrated circuits 13 may be connected to the conductive layer when thethin film integrated circuits 13 are bonded to the second sheet member19 or the third sheet member 23.

Embodiment 2

In this embodiment, the structure of an IC sheet (also referred to as anIC film, a sheet member, or a film member) is explained hereinafter.

As illustrated in FIG. 5, the IC sheet is a sheet formed by interposingto seal each of thin film integrated circuits 13 between two sheetmembers 19 and 23. The IC sheet is obtained by interposing to seal aplurality of thin film integrated circuits between the second sheetmember 19 and the third sheet member 23 as shown in Embodiment 1.

Each of the thin film integrated circuits 13 has a plurality of elementsand a conductive layer serving as an antenna. Moreover, each of the thinfilm integrated circuits 13 can be regularly arranged to be a sheet bypeeling effectively the thin film integrated circuits provided over thesubstrate (FIG. 5A). Further, one IC sheet may be rolling up in a rolleror may be folded back on itself (FIG. 5B).

As noted above, it is easy to ship the sheet-like IC sheet including aplurality of the thin film integrated circuits 13 sealed with a pair ofsheet members. Particularly, the IC sheet is effective in shipping inthe case of manufacturing a large quantity of the thin film integratedcircuits 13. A plurality of the thin film integrated circuits 13 cut inpieces has a difficulty in handling. The handling of the IC sheetaccording to this embodiment is easy since the IC sheet is formed to besheet-like. In addition, the IC sheet according to this embodiment canprotect the thin film integrated circuits 13 from being damaged andbroken. When one wants to remove the thin film integrated circuits 13individually from the IC sheet, the thin film integrated circuits 13 maybe cut by a dicing machine, scribing machine, a laser irradiationmachine (CO₂ laser irradiation machine), or the like.

This embodiment can be freely combined to the foregoing embodiments.

Embodiment 3

In this embodiment, the structure of a scroll of an IC sheet isexplained hereinafter.

As illustrated in FIG. 6, the scroll of the IC sheet is formed byreeling a sheet member. Specifically, the scroll of the IC sheet isformed by reeling a plurality of thin film integrated circuits 13 whichis interposed to be sealed between two sheet members 19 and 23 to be aroll. As described in Embodiment 1, the scroll of the IC sheet isobtained by reeling by a roller to collect the sheet-like plurality ofthin film integrated circuits 13 sealed with a second sheet member 19and a third sheet member 23. Each of the thin film integrated circuits13 has a plurality of elements and a conductive layer serving as anantenna. Moreover, each of the thin film integrated circuits 13 isregularly arranged.

As noted above, it is easy to ship the scroll of the IC sheet formed byreeling the thin film integrated circuits 13 sealed with a pair of sheetmembers. Particularly, the scroll of the IC sheet is effective inshipping in the case of manufacturing a large quantity of the thin filmintegrated circuits 13. Generally, a plurality of the thin filmintegrated circuits 13 cut in pieces has a difficulty in handling. Thehandling of the scroll of the IC sheet according to this embodiment iseasy since the IC sheet is reeled to be a scroll. For example, the thinfilm integrated circuits 13 can be used in a state as illustrated inFIG. 6B. In addition, the IC sheet according to this embodiment canprotect the thin film integrated circuits 13 from being damaged andbroken by using in such a way as noted above.

This embodiment can be freely combined to the foregoing embodiment.

Embodiment 4

In this embodiment, a method for manufacturing an IC chip according tothe present invention is explained hereinafter with reference to thedrawings.

A peeling layer 101 is formed on a substrate 100 (FIG. 7A). As thesubstrate 100, a glass substrate such as barium borosilicate glass oralumino-borosilicate glass, a quartz substrate, a ceramic substrate, orthe like can be used. A semiconductor substrate such as a metalsubstrate including stainless or a silicon substrate over which aninsulating film is formed can be used. A substrate made from syntheticresin such as plastic having flexibility has generally a lower allowabletemperature limit than that of the foregoing substrate; however it canbe used only in the case that it can resist processing temperature in amanufacturing process. The surface of the substrate 100 may be smoothedby polishing such as a CMP method. When using the silicon substrate, thepeeling layer 101 is not required to be provided.

The peeling layer 101 is formed by forming a layer containing silicon bya sputtering method, a plasma CVD, or the like. The layer containingsilicon corresponds to an amorphous semiconductor film includingsilicon, a semiamorphous semiconductor film which is a mixture of anamorphous state and a crystalline state, a crystalline semiconductorfilm, or the like. As the peeling layer 101, a film containing metal canbe used. For example, as a metal film and a metal oxide film, W and WOx,Mo and MoOx, Nb and NbOx, Ti and TiOx (x=2, 3), or the like can beformed respectively. Here, the peeling layer 101 is formed all over thesubstrate 100; alternatively, it may be formed selectively on thesubstrate 100.

The peeling layer 101 is formed directly on the substrate 100 in thisembodiment. A base film can be formed between the substrate 100 and thepeeling layer 101. The base film may be a single layer structure or alaminate layer structure of an insulating film containing oxygen ornitrogen such as silicon oxide (SiOx), silicon nitride (SiNx), siliconoxynitride (SiOxNy) (x>y), or silicon nitride oxide (SiNxOy) (x<y) (x,y=1, 2 . . . ). Particularly, in the case that there is fear that thesubstrate is contaminated, the base film is preferably formed betweenthe substrate 100 and the peeling layer 101.

An insulating film 102 as a base film is formed over the peeling layer101. The insulating film 102 can be formed to have a single layeredstructure or a laminate layered structure. For example, the insulatingfilm may be formed to have a laminated layered structure composed ofthree layers, for example, a silicon oxide film as a first insulatingfilm, a silicon nitride oxide film as a second insulating film, and asilicon oxynitride film as a third insulating film.

An element group 103 is formed over the insulating film 102. As theelement group 103, for example, one or a plurality of thin filmtransistors, capacitor elements, resistance elements, diodes, or thelike. FIG. 7 illustrates that a thin film transistor having a GOLDstructure is formed as the element group 103; however, the thin filmtransistor may be formed to have an LDD structure by forming a side wallat the side face of a gate electrode.

An insulating film 104 is formed so as to cover the element group 103.An insulating film 105 is formed over the insulating film 104. Then, aconductive layer 106 serving as an antenna is formed over the insulatingfilm 105. Thereafter, an insulating film 107 serving as a protectivefilm is formed over the conductive layer 106. After performing theforegoing processes, thin film integrated circuits 108 including theelement group 103 and the conductive layer 106 are completelymanufactured.

An inorganic insulating film or an organic insulating film can be usedfor the insulating films 104, 105, and 107. As the inorganic insulatingfilm, a silicon oxide film or a silicon oxynitride film formed by a CVDmethod or a silicon oxide film coated by an SOG (Spin On Glass) method.As the organic insulating film, a film made from polyimide, polyamide,BCB (benzocyclobutene), acrylic, positive type photosensitive organicresin, negative type organic resin, or the like can be used. A laminatedstructure of an acrylic film and a silicon oxynitride film can be used.

The insulating films 104, 105, and 107 can be formed by siloxane resin.The siloxane resin corresponds to resin including a Si—O—Si bond.Siloxane is composed of a skeleton formed by the bond of silicon (Si)and oxygen (O), in which an organic group containing at least hydrogen(such as an alkyl group or aromatic hydrocarbon) is included as asubstituent. Alternatively, a fluoro group may be used as thesubstituent. Further alternatively, a fluoro group and an organic groupcontaining at least hydrogen may be used as the substituent.

The siloxane resin can be classified into silica glass, alkylsiloxanepolymer, alkylsilsesquioxane polymer, hydrogenated silsesquioxanepolymer, hydrogenated alkylsiloxane polymer, and the like. An interlayerinsulating film can be formed by a material containing polymer(polysilazane) having a Si—N bond.

Opening portions 111, 112 are formed so that the peeling layer 101 isexposed between the thin film integrated circuits 108 (FIG. 7B). Theopening portions 111, 112 are formed by etching or dicing with a mask.FIG. 10A is a top view for showing this state. The cross-sectional viewin FIGS. 7A to 7C corresponds to FIG. 10A taken along line A-B.

An etching agent for removing the peeling layer 101 is introduced intothe opening portions 111, 112 to remove the peeling layer graduallyexcept parts of the peeling layer 113 to 115 (FIGS. 7C and 10B). As theetching agent, gas or liquid containing halogen fluoride is used. Forexample, halogen trifluoride (ClF₃) is used as halogen fluoride.

As noted above, the peeling layer 101 is not completely removed in thisprocess to leave the parts of the peeling layer 113 to 115 located belowthe thin film integrated circuits 108. Accordingly, the thin filmintegrated circuits 108 can be prevented from dispersing to bescattered, which leads to keep the arrangement as before being peeledeven after being peeled. In the case that there is no fear of dispersingthe thin film integrated circuits 108, peeling can be carried out afterremoving the peeling layer 101 completely.

First surfaces of the thin film integrated circuits 108 are bonded to afirst sheet member 116. Accordingly, the thin film integrated circuits108 are peeled from the substrate 100 (FIG. 8A). As noted above, in thecase that the thin film integrated circuits 108 are physically peeledfrom the substrate 100 while leaving the parts 113 to 115 of the peelinglayer 101, a metal film is preferably formed over the peeling layer 101.For example, in the case of using W or Mo as a peeling layer, a siliconoxide film is formed over the W or Mo, and WOx or MoOx is respectivelyformed over the W or Mo by heat treatment or the like. By forming themetal oxide film, the peeling layer becomes easily to be peeled from thesilicon oxide film, and the substrate and the thin film integratedcircuit can be easily separated without removing completely the peelinglayer. Further, the first sheet member 116 is formed by a flexible film,and an adhesive agent is provided to at least a surface of the firstsheet member 116 which is in contact with the thin film integratedcircuits 108. For example, a film formed by forming a film provided withan adhesive agent having poor adhesion containing acrylic resin over abase film made from polyester or the like can be used.

Second surfaces of the thin film integrated circuits 108 are bonded tothe second sheet member 117 to peel the thin film integrated circuits108 from the first sheet member 116 (FIG. 8B).

A third sheet member 118 is bonded to the surface of the thin filmintegrated circuits 108 opposite to the surface bonded with the secondsheet member 117, simultaneously, the thin film integrated circuits 108are sealed with the second sheet member 117 and the third sheet member118 (FIG. 8C). Accordingly, the thin film integrated circuits 108 aresealed with the second sheet member 117 and the third sheet member 118.The second sheet member 117 and the third sheet member 118 are formed byflexible films such as laminate films. Specifically, a hot melt filmformed over a base film such as polyester can be used. Either or both ofpressure treatment and heat treatment is carried out when bonding thesecond sheet member 117 and the third sheet member 118 to the thin filmintegrated circuits 108, which can make it possible to bond the thinfilm integrated circuits 108 in a short time.

The second sheet member 117 and the third sheet member 118 are cutselectively between the thin film integrated circuits 108 by dicing,scribing, or a laser cut method. Accordingly, a sealed IC chip iscompletely manufactured (FIGS. 9A and 9B).

The sealed IC chip completed through the foregoing processes has a sizeof 5 mm square (25 mm²) or less, preferably, 0.3 mm square (0.09 mm²) to4 mm square (16 mm²).

Since the chip according to the present invention in the case of notusing a silicon substrate uses a thin film integrated circuits formedover an insulating substrate, there are no constraints on the shape of amother substrate unlike a chip formed from a circular silicon substrate.Accordingly, the productivity of the chip can be improved, and so massproduction can be realized. The peeled substrate can be reused in theabove process. The costs for manufacturing a thin film integratedcircuit using a substrate such as glass can be reduced. For example,there is a problem of high prime costs of a quartz substrate despite itsadvantages in flatness and high heat resistance. Reusing the substrateleads to the reduction of the costs even in the case of using the quartzsubstrate which costs more than the glass substrate. In this embodiment,a thin film integrated circuit is formed over the quartz substrate, andthe thin film integrated circuit is peeled, then, the quartz substrateis reused. Therefore, a thin film integrated circuit having highercharacteristics can be manufactured at low costs.

Since the IC chip explained in this embodiment uses a semiconductor filmhaving a thickness of 0.2 μm or less, typically, 40 to 170 nm,preferably, 50 to 150 nm as an active region, the IC chip is formed tobe extremely thin shaped. As a result, tampering can be prevented sincethe thin film integrated circuits are hardly recognized in the state ofbeing mounted to an article. Further, there is no fear of radio waveabsorption, and so a high-sensitive signal can be received unlike an ICchip formed by a silicon substrate. The thin film integrated circuitwhich does not have a silicon substrate has a light transmittingproperty. Consequently, the thin film integrated circuit can be used forvarious articles. For example, the thin film integrated circuits can bemounted to a print surface of an article, which does not detract fromthe design of the article.

This embodiment can be freely combined to the foregoing embodiments.

EXAMPLE 1

In this example, a method for manufacturing a gate electrode in a methodfor manufacturing an ID chip explained in the foregoing Embodiments isexplained with reference to FIGS. 15A to 16B. If not otherwisespecified, the gate electrode can be manufactured by using the samematerial as that described in Embodiments.

Firstly, a peeling layer 201 is formed over a substrate 200 to providesemiconductor films 211, 212 via insulating layers 202, 203. Further, agate insulating film 213 is formed over the semiconductor films 211,212. Thereafter, a first conductive layer 951 and a second conductivelayer 952 are stacked over the gate insulating film 213. In thisexample, tantalum nitride (TaN) is used for the first conductive layerand tungsten (W) is used for the second conductive layer. The TaN filmmay be formed by a sputtering method using a target of tantalum in anitrogen atmosphere. The W film may be formed by a sputtering methodusing a target of tungsten.

In this example, the first conductive layer 951 is made from TaN and thesecond conductive layer 952 is made from W. However, the materials forthe first conductive layer 951 and the second conductive layer 952 arenot restricted to the TaN and the W. Elements selected from Ta, W, Ti,Mo, Al, Cu, Cr, and Nd; an alloy material or a compound material, eachof which contains mainly the foregoing elements, can be used.Alternatively, a semiconductor film as typified by a polycrystallinesilicon film doped with an impurity element such as phosphorus. Furtheralternatively, AgPdCu alloys can be used. Combinations of the conductivelayers can be appropriately selected. The first conductive layer 951 maybe formed to have a thickness in the range of from 20 to 100 nm. Thesecond conductive layer 952 may be formed to have a thickness in therange of from 100 to 400 nm. In this example, the conductive layers areformed to have a laminated structure of two layers. Alternatively, asingle layered conductive layer may be formed, or the conductive layersmay be formed to have a laminated structure of three or more layers.

Then, resist 953 is selectively formed over the second conductive layer952 by a photolithography method or a droplet discharging method (FIG.15A). Thereafter, the resist 953 is etched by known etching treatmentsuch as O₂ (oxygen) plasma to reduce the size of the resist 953 (FIG.15B). When etching the first conductive layer 951 and the secondconductive layer 952 using the reduced resist 954 as a mask, a gateelectrode having a further reduced width can be formed. That is, a gateelectrode having a further smaller width can be formed than that of agate electrode formed by using a resist 953 which is obtained by usualpatterning. In such a way, the width of a channel formation region isreduced by reducing the size of a gate electrode structure. Accordingly,a high speed operation becomes possible.

A method for manufacturing a gate electrode which is different from thatillustrated in FIGS. 15A and 15B is explained with reference to FIGS.16A and 16B.

As shown in FIG. 15A, the peeling layer 201, the insulating films 202,203, the semiconductor films 211, 212, the gate insulating film 213, thefirst conductive layer 951, and the second conductive layer 952 arestaked. Then, the resist 953 is selectively formed. And then, the firstconductive layer 951 and the second conductive layer 952 are etchedusing the resist 953 as a mask (FIG. 16A). According to the process, agate electrode 956 is formed by the first conductive layer 951 and thesecond conductive layer 952. Thereafter, the gate electrode 956 isetched by an etching method. Since the resist 953 is provided over thegate electrode 956, the sides of the gate electrode 956 are etched;accordingly, a gate electrode 957 having a smaller width than that ofthe gate electrode 956 can be formed as shown in FIG. 16B.

According to the manufacturing method explained in this example, a smallgate electrode having the size over the limit of patterning by aphotolithography method or the like can be manufactured. By minimizingthe gate electrode, smaller element structure can be provided.Accordingly, more elements can be formed, and so a circuit having highperformance can be formed. Further, a thin film integrated circuit (ICchip or the like) can be miniaturized in the case that the thin filmintegrated circuit is formed to have the same numbers of elements asbefore. The method illustrated in FIGS. 15A and 15B and the methodillustrated in FIGS. 16A and 16B can be combined to form further smallgate electrode.

This example can be implemented by freely combining to the foregoingEmbodiments.

EXAMPLE 2

In this example, the structure of a TFT layer 102 which is differentfrom that described in Example 1 with reference to FIG. 14.

FIG. 14 shows a structure which is the structure of an element structure103 in FIG. 7A added with a bottom electrode. That is, as shown in FIG.14, a structure 519 including a channel region of a semiconductor film311 interposed between the bottom electrode 513 and a gate electrode 214via an insulating film.

The bottom electrode 513 can be formed by metal or a polycrystallinesemiconductor added with an impurity of one conductivity type. In caseof using metal, W, Mo, Ti, Ta, Al or the like can be used. Further, asilicon nitride film 514 and a silicon oxynitride film 515 which serveas base insulating films are formed. The materials and the laminationorder of the silicon nitride film 514 and the silicon oxynitride film515 are not restricted to those as described herein.

As noted above, a TFT having a bottom electrode can be used as thestructure of the TFT layer 102. Generally, when the size of the TFT isreduced and a clock frequency for operating a circuit is improved, powerconsumption of an integrated circuit is increased. Therefore, a methodof applying a bias voltage to the bottom electrode is useful indeterring the increase of the power consumption. By varying the biasvoltage, a threshold voltage of the TFT can be varied.

Applying a minus bias voltage to the bottom electrode of an n-channelTFT increases a threshold voltage with a decrease in leakage. On theother hand, applying a plus bias voltage decreases the thresholdvoltage, which leads to easier flow of current through the channel andoperation of the TFT at high speed or at low voltage. Further, applyinga plus bias voltage to the bottom electrode of a p-channel TFT increasesa threshold voltage with a decrease in leakage. On the other hand,applying a minus voltage decreases the threshold voltage, which leads toeasier flow of current through the channel and operation of the TFT athigh speed or at low voltage. By controlling a bias voltage for applyingto the bottom electrode, the characteristics of an integrated circuitcan be drastically improved.

By balancing the threshold voltage of the n-channel IN and the p-channelTFT with the bias voltage, the characteristics of an integrated circuitcan be improved. In that case, both of a power source voltage and thebias voltage for applying to the bottom electrode can be controlled inorder to reduce power consumption. When the circuit is in a standbymode, a large reverse direction bias voltage is applied to the bottomelectrode. In operation, a weak reverse direction bias voltage isapplied to the bottom electrode when load is small, whereas a weakforward bias voltage is applied when the load is large. The applicationof the bias voltage may be made be capable of being switched dependingon the state of operation or load of the circuit by providing a controlcircuit. By controlling power consumption or TFT performance in such away, circuit performance can be maximized.

This example can be freely combined to the foregoing Embodiments andExamples.

EXAMPLE 3

In this example, the structure of an IC chip manufactured by amanufacturing method according to the present invention is explained.

FIG. 11A is a perspective view of one form of an IC chip. Referencenumeral 920 denotes an integrated circuit and 921 denotes an antenna.The antenna 921 is electrically connected to the integrated circuit 920.Reference numeral 922 denotes a substrate and 923 denotes a covermember. The integrated circuit 920 and the antenna 921 are sandwichedbetween the substrate 922 and the cover member 923.

FIG. 11B shows one form of a functional structure of the IC chipillustrated in FIG. 11A.

In FIG. 11B, reference numeral 900 denotes an antenna; 901, anintegrated circuit; and 903, a capacity formed between terminals of theantenna 900. The integrated circuit 901 has a demodulation circuit 909,a modulation circuit 904, a rectification circuit 905, a microprocessor906, a memory 907, and a switch 908 for giving load modulation to theantenna 900. There may be more than one memory 907. A plurality ofmemories such as an SRAM, a flash memory, a ROM, an FRAM (registeredtrademark), and the like can be used.

A signal sent from a reader/writer as an electric wave is converted intoan alternating electric signal by electromagnetic induction in theantenna 900. The demodulation circuit 909 demodulates the alternatingelectric signal to send it to the microprocessor 906 in a subsequentstage. The rectification circuit 905 generates power source voltage bythe alternating electric signal to supply it to the microprocessor 906in the subsequent stage. The microprocessor 906 carries out variouskinds of arithmetic processing according to an inputted signal. Thememory 907 stores a program and data used in the microprocessor 906. Thememory 907 can be used as a working area in the arithmetic processing.

When data is sent from the microprocessor 906 to the modulation circuit904, the modulation circuit 904 can control the switch 908 to apply loadmodulation to the antenna 900 according to the data. As a result, thereader/writer can read out the data from the microprocessor 906 byreceiving the load modulation given to the antenna 900.

The IC chip does not always have to have the microprocessor 906. Thetransmission system of a signal is not restricted to the foregoingelectromagnetic coupling system as shown in FIG. 11B. Theelectromagnetic system, a microwave system, or another transmissionsystem can be used.

Since an IC chip having an antenna can transmit external information,the IC chip can be used as a wireless memory or a wireless processor.

This example can be freely combined to the foregoing Embodiments andExamples.

EXAMPLE 4

In this example, the usage of a thin film integrated circuit describedin the foregoing Embodiment or Examples is explained. The thin filmintegrated circuit peeled from a substrate can be used as an IC chip210, for example, paper money, coins, securities, bearer bonds,certificates (driver's license, resident card, and the like, refers toFIG. 12A), packing containers (wrapping paper, bottle, and the like,refers to FIG. 12B), recording media such as a DVD software, a CD, or avideo tape (FIG. 12C), vehicles such as a car, a motorbike, or a bicycle(FIG. 12D), commodities such as a bag or glasses (FIG. 12E), foods,garments, consumption goods, electric appliances, and the like. Theelectric appliance indicates a liquid crystal display device, an ELdisplay device, a television apparatus (referred to as a television ortelevision set), a cellular phone, and the like.

The IC chip can be fixed to an article by pasting onto the surface ofthe article or embedding in the article. For example, the IC chip may beembedded in a paper of a book or in organic resin of a package made fromthe organic resin. Counterfeiting can be prevented by providing the ICchip to paper money, coins, securities, bearer bonds, certificates. Aninspection system or a system used in a rental shop can be made moreefficient by providing the IC chip to packing containers, recordingmedia, commodities, foods, garments, consumption goods, electricappliances, and the like. Imitation or theft can be prevented byproviding the IC chip to vehicles.

By applying the IC chip to a system for management or distribution ofgoods, the system can be made sophisticated. For example, as shown inFIG. 13A, the case that a reader/writer 295 is provided to the side faceof a portable terminal having a display portion 294 and the case that anIC chip 296 is provided to the side face of an article 297 (FIG. 13A)are taken as an example. In that case, when the IC chip 296 is held overthe reader/writer 295, information on the raw material, the place oforigin, and the history of a distribution process of the article 297 isdisplayed on the display portion 294. As another example, in the casethat the reader/writer 295 is provided beside a belt conveyor,inspection of the article 297 provided with the IC chip 296 can beeasily carried out (FIG. 13B).

This example can be implemented by combining freely with the foregoingEmbodiments and Examples.

What is claimed is:
 1. An IC sheet comprising: a plurality of thin filmintegrated circuits; and two sheet members for sealing each of aplurality of thin film integrated circuits between the two sheetmembers, wherein each of the plurality of thin film integrated circuitshas a plurality of thin film transistors and a conductive layer servingas an antenna.
 2. The IC sheet according to claim 1, wherein each of theplurality of the thin film integrated circuits is regularly arranged. 3.The IC sheet according to claim 1, wherein the two sheet members arelaminate films.
 4. An IC sheet comprising: wounded two sheet memberswhich seal each of a plurality of thin film integrated circuits betweenthe two sheet members, wherein each of the plurality of thin filmintegrated circuits has a plurality of thin film transistors and aconductive layer serving as an antenna.
 5. The IC sheet according toclaim 4, wherein each of the plurality of the thin film integratedcircuits is regularly arranged.
 6. The IC sheet according to claim 4,wherein the two sheet members are laminate films.
 7. A method formanufacturing an IC chip comprising the steps of: forming a peelinglayer over a substrate having an insulating surface; forming a pluralityof thin film integrated circuits over the substrate; forming an openingportion at a boundary between the thin film integrated circuits toexpose the peeling layer; introducing gas or liquid containing halogenfluoride into the opening portion to remove the peeling layer; bondingfirst surfaces of the thin film integrated circuits to a first sheetmember to peel the thin film integrated circuits from the substrate;bonding second surfaces opposed to the first surfaces of the thin filmintegrated circuits to a second sheet member to peel the thin filmintegrated circuits from the first sheet member; bonding the firstsurfaces of the thin film integrated circuits to a third sheet member toseal the thin film integrated circuits with the second sheet member andthe third sheet member.
 8. The method for manufacturing an IC chipaccording to claim 7, wherein a plurality of thin film transistors and aconductive layer serving as an antenna are formed as the thin filmintegrated circuits over the substrate.
 9. A method for manufacturing anIC chip comprising the steps of: forming a plurality of thin filmintegrated circuits over a substrate; bonding first surfaces of the thinfilm integrated circuits to a first sheet member to peel the thin filmintegrated circuits from the substrate; bonding second surfaces opposedto the first surfaces of the thin film integrated circuits to a secondsheet member to peel the thin film integrated circuits from the firstsheet member; and bonding the first surfaces of the thin film integratedcircuits to a third sheet member to seal the thin film integratedcircuits with the second sheet member and the third sheet member. 10.The method for manufacturing an IC chip according to claim 9, wherein aplurality of thin film transistors and a conductive layer serving as anantenna are formed as the thin film integrated circuits over thesubstrate.